As the electronic technologies advance quickly, generational shifts of electronic products also accelerate day by day. During use, most electronic products need to be charged to maintain normal operation.
In the prior art, a mobile phone is basically charged at a fixed current, and a fixed current charging process may be divided into three stages: trickle charging, constant current charging, and constant voltage charging. Trickle charging is first performed; when a charging voltage during the trickle charging reaches a predetermined voltage of constant current charging, constant current charging is performed; when the charging voltage during the constant current charging reaches a predetermined voltage of constant voltage charging, constant voltage charging is performed. For example, a current of trickle charging uses 100 milliamp (mA), a current of constant current charging uses 1 amp (A), and a voltage of constant voltage charging uses 4 volts (V).
In the process of implementing charging, the inventor finds that the prior art at least has the following problems.
When a charger charges a high-current mobile phone at an early stage, a current at a constant current stage uses a fixed high current value in the charging process; because a load current of the charger is small at the early stage, if the charger is in a high-current state, a short circuit phenomenon of the charger is caused.